Apparatus for administering injectable liquids



I Umted States Patent [1113,548,826

[ 72] Inventor Chll'l J. Wilson [56] References Cited 1626 N. Prospect,Milwaukee, Wis. 53202 UNITED STATES PATENTS I211 APPI- 8431250 1,718,6036/1929 Smith 128/218 1 FM 98 .7 8 1967 2,655,919 10/1953 GOOdSICinetal.... l28/2l8 636,932 May 1 1 2,789,559 4/1957 Breitenbach 128/218Patent N0. 3,495, 2,895,474 7/1959 Reznek 128/218 [451 Paemed 3,026,8733/1962 Miskel et al. 128/218 3,089,489 5/1963 Dunmire 128/216 J 54APPARATUS FOR ADMINISTERING INJECTABLE 3,224,445 12/1965 Melon 128/218LIQUIDS Primary Examiner-Warner H. Camp 1 Chill! 8 Drawing 8Attorney-Hill, Sherman, Meroni, Gross and Simpson [52] US. (I 128/218, 128/ 272 [51] ll. Cl. A61"! 5/24,

A6 1 j l [06 ABSTRACT: A transparent cartridge containing injectable[50] Field of Search 128/218, liquid prepackaged under a negativepressure to afford completely automatic aspiration when used in asyringe.

PATENTEnnEcwsm 3,548,826

saw 1 OF 2 ATTORNEYS PATENTED BEC22 I970 SHEET 2 OF 2 APPARATUS FORADMINISTERING INJECTABLE LIQUIDS RELATED APPLICATION This application isa division of my parent application Ser. No. 636,932 filed May 8, 1967,and now U.S. Pat. No. 3,495,591.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates generally to carpules and more particularly to prepackagedcartridges filled with injectable liquid for injection.

2. Description of the Prior Art It is known in the art to provide bloodsample collection apparatus with evacuated vials so that a blood samplewill be drawn uponinserting a syringe into a blood vessel. See U.S. Pat.Nos. 3,141,460 and 3,143,109. 7

It is also known in the art to aspirate a syringe before injectingliquid medicine subcutaneously to avoid accidental adverse reactions toinjectable liquids such as drugs or anesthetic. One such reaction may becaused, for example, by the injection of a liquid directly into thelumen of a blood vessel. For example, if a cardiac patient were toreceive an injection of a liquid anesthetic directly into a vein orartery, a fatal stimulation may occur.

Prior art practitioners have attempted to solve the problem bymechanical aspiration devices of various types.

For example, the plunger of a syringe is pushed by thumb pressureagainst the cartridge piston of a carpule after the point of the needlehas been inserted into the tissue of the a patient. This forces thediaphragm at the front end of the cartridge against the rearend of theneedle. Since the pressure required to move the sealing piston into thecartridge is greater than the pressure required for the needle to piercethe diaphragm, the rear end of the needle penetrates the diaphragm sothat the hollow of the needle then communicates with the interior of thecartridge. 1 I

A small harpoon or hook formed on the end of the plunger is depressedinto the piston, so that a reverse pressure on the plunger has theeffect of pulling the piston backwardly slightly to cause a negativepressure in the cartridge for purposes of aspiration.

Several difficulties are encountered in attempting to use mechanicalaspiration. One such difficulty arises in pulling the plunger andsealing piston backward by thumb pressure after the preliminary quantityof drugs has been discharged from the cartridge. While the thumb canexert great pressure when acting in the direction of the forefinger, itis extremely difficult to apply a pressure in the opposite direction.Furthermore, the effort required may cause movement of the entiresyringe including the needle while it is embedded in the tissue. Also,as the plunger and the sealing piston are being pulled backwardly tocreate a vacuum in the cartridge for the visual blood check the plungermay be pulled back so far that the piston comes out of the cartridgebody.

Other prior art practitioners have used supplemental vacuum generatorsin combination with syringes. Such devices cannot be used withconventional syringes and oftentimes require provision of clumsycumbersome devices which are difiicult to operate. See U.S. Pat. Nos.2,771,879, 2,971,509 and 3,089,489. 1 t

A serious deficiency of any mechanical aspirator, of course, is inherentin the fact that the operator may inadvertently overlook the need ofaspiration or may negligently avoid the use thereof.

It is contemplated by the present invention that a prepackaged carpuleor transparent cartridge containing injectable liquid be packaged andmaintained under a discreet 7 negative pressure. Thus, as one end of thecarpule or cartridge is punctured by the rear end of the needle orcannula it is immediately and automatically subjected to a negativepressure condition, and if the point of the needle or cannula is lodgedin a blood vessel a quantity of blood is immediately drawn into thecartridge as a tell-tale where it canbe readily observed.

It is, therefore, an object of the present invention to provide animproved apparatus for administering injectable liquids.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view ofa plunger-type syringe constructed in accordance with the principles ofthe present invention and having a prepackaged injectableliquid-containing cartridge placed within the barrel of the cartridgeand showing the plunger in a fully retracted position.

FIG. 2 is an enlarged front elevational view of a needle assembly of thesyringe.

FIG. 3 is an elevational view of the syringe with the needle assemblyremoved and with the barrel cocked to permit breech-loading of acartridge.

FIGS. 4 and 5 are respectively elevational front and end views of acarpule or cartridge constructed in accordance with this invention andprepackaged under negative pressure.

FIGS. 6a-6c show the syringe in different stages in the ad ministeringof an injectable liquid with the tissue situs shown in cross section.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention providesthe advantages of completely automatic aspiration with any conventionalsyringe structure.

Referring to FIGS. 1-3, a typical plunger-type syringe with which theprinciples of this invention may be practiced is indicated generally atreference numerallO and comprises a tubular housing or barrel 11, aneedle assembly 12 at one end of thebarrel 11, a spool finger grip 13 atthe other end of the barrel l1 and a plunger 14 mounted for movementinto and out of the barrel 11. A thumb ring 16 is formed at the distalend of the plunger 14 to receive the thumb of the user, and finger grip13 is spool-shaped to receive the fore and middle fingers of the user.

The needle assembly 12 comprises a body 15 internally threaded to bescrewed onto a threaded stud l7 projecting from the needle end of thebarrel 1]. Acannula or hollow needle 18 extends through the body 15 andis pointed at a forward end 19 to reduce the force necessary to insertthe tip of the needle into the tissue. A rear end 20 of the needleextends substantially beyond the body 15 and may also be pointed ifdesirable to facilitate puncture of the cartridge diaphragm as willbecome apparent hereinafter. v

The syringe 10 is of the cocking type, that is, the plunger 14 ismounted for articulation with respect to the barrel 11 to enable thedrug-containing cartridge tobe inserted into a rear or loading end 21 ofthe barrel. The present invention, however, is applicable to all of theplunger-type syringes which accommodate the prepackaged cartridgesregardless of the means by which the cartridge is loaded into thesyringe.

In the illustrated embodiment a bifurcated bracket 22 extends from thefinger grip 13 and comprises a pair of aligned pins as at 23 received incomplemental bores formed in the barrel 11 for accommodating pivotalmovement of the barrel with respect to the finger grip l3 and theplunger 14.

A plurality of openings or windows as indicated at 24 and 26 are formedin the barrel 11 to enable the user to see into the barrel. An enlargedhead 27 is formed at the inner end of the plunger 14 and a threadedinsert 28 is received in a complementarily threaded bore formed in thefinger grip 13. A por- Referring to FIGS. 4 and 5 a carpule or cartridgeconstructed according to the principles of this invention is indicatedgenerally at reference numeral 30. The carpule or cartridge comprises atubular enclosure wall 31 having a reduced diameter neck 32 and anenlarged head 33. The cartridge 30 is substantially filled with aninjectable liquid 34 and a rear end 36 of the cartridge 30 is closed bymeans of a resiliently expansible seal piston or stopper 37 and afrontend or nose 38 is closed by a needle-pervious self-sealing wallmember 39. The piston 37 may be made of rubber and the needle-perviouswall member 39 may constitute a rubber diaphragm.

In filling and sealing the cartridge 30, the liquid 34is filled andconfined within the interior of the cartridge under a negative pressure.The piston or stopper 37 effectively seals the liquid to store the sameunder avacuum condition within the cartridge 30. It is contemplated thatthe quantum of negative pressure be within the range normally producedby mechanical aspiration since it would not be necessary to attainnegative pressures in an amount provided in blood sample collectionevacuated vials.

In use, the barrel 1-1 of the syringe is first cocked as shown in FIG. 3and a cartridge 30 exhibiting the characteristics of this invention isloaded head first into the barrel 11. The barrel is then articulatedinto the aligned position thereof shown in FIG. 1 and the insert 28threaded into the finger grip 13 to lock the barrel 11 in place. Thecartridge 30 then resides within the barrel 11 in the position thereofshown in FIG. 1. The user then places the fore and middle fingers of thehand across the spool finger grip 13 and the thumb through the ring 16.

With the plunger 14 still in a retracted position, the needle 18 isinserted into the tissue situs by penetrating the epidermis and making asubcutaneous placement of the end of the cannula. Thumb pressure is thenapplied to the plunger 14 to move the plunger head 27 into abuttingengagement with the sealing piston 37. Further pressure on the plunger14 moves the cartridge forwardly until the diaphragm 39 abuts the rearend of the needle 18.

An added force is then applied to the plunger 14 to cause the rear end20 of the needle to pierce the diaphragm 39 and as this occurs thehollow of the needle 18 is immediately subjected to a negative pressurewithout any further mechanical actuation whatsoever. If the point 19 ofthe needle 18 is improperly-placed in the lumen of a blood vessel astream of blood will be drawn into the cartridge 30. The wall 31 of thecartridge is at least partly constructed of glass, clear plastic orother transparent material so that the traces of blood within thecartridge will constitute a tell-tale and can be easily observed by theuser.

Assuming no traces of blood are seen within the cartridge 30, the userapplies additional thumb pressure to the plunger 14 to push the sealingpiston 37 toward the head portion 33 of the cartridge 30, thus expellingthe drugs 34 from the cartridge, through the hollow of the needle 18 andinto the tissue. In this respect it is noted than that the diameter ofthe plunger head portion 27 is less than the diameter of the piston 37so that it may travel into the tubular wall 31, and it is further notedthat the needle 18 and the cartridge are constructed and arranged sothat the force required for the rear end 20 of the needle 18 to pierceand penetrate the diaphragm 39 is less than that required to push thepiston 37 into the tubular wall 3'].

FIGS. 6a 6c illustrate the relative disposition of the parts of thesyringe in various stages of an injection. In FIG. 6a the needle 18 hasbeen inserted into tissue Unbeknownst unbeknownst to the user, however,the point 19 is lodged in the lumen of a blood vessel 41. This fact ismade known, however, as soon as the rear end of the needle punctures andpenetrates the diaphragm 39 of the cartridge 30 since tell-tale tracesof blood as indicated at 42 are observed within the cartridge and cloudthe contents of the carpule with a distinctive blood red color. Theneedle 18 is then removed from the tissue 40 and a fresh cartridge isloaded into the sginge It).

FIG. 6b 1] ustrates the needle 1 again inserted into the tissue 40-butthis time the point of the needle is not lodged in a blood vessel. Thus,as the plunger 14 is depressed and the rear end 20 of the needle 18punctures the diaphragm 39, automatic aspiration again takes placewithout any special effort on the part of the user. In this instanceplacement of the cannula is proper if no traces of blood are observed inthe cartridge 30 through the window 24. The plunger 14 is then furtherdepressed as shown in FIG. 6c to expel the liquid 34 from the cartridge30 through the hollow of the needle 18 and into the tissue 40.

It is thus apparent that the present invention enables the user of thesyringe to check, placement of the cannula automatically withoutresorting to mechanical aspirating techniques of any kind.

Injection terminology uses expressions such as subcutaneous," meaningwithin the cutaneous tissues; "intradermal" meaning within theepidermis, and intravenous," meaning within a vein. Aspiration isrequired in all types of injections. In a subcutaneous injectionaspiration insures placement outside of a blood vessel. Those versed inthe art will recognize that the present invention may also be useful inassuring the user that an intravenous injection is properly placedinside the blood vessel.

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon all such modifications as reasonably comewithin the scope of my contribution to the art.

I claim:

1. For use in a plunger-type syringe having:

a tubular barrel open to atmosphere with the rear or inner end of ahollow needle at one end thereof and the head end of a finger-operatedplunger at the opposite end thereof;

a container comprising an elongated tubular wall made of transparentmaterial;

a piston closing one endof said container and having an outer walldirectly engageable with the head end of said plunger;

a penetrable diaphragm closing the other end of said container;

a supply of liquid fully prepared for direct injection filling saidcontainer and reduced in pressure to a pressure below atmosphericpressure;

said diaphragm communicating directly on one side thereof with theatmospheric air in the barrel and communicating on the other sidethereof directly with the reduced pressure liquid within said container;and

the inner end of the hollow needle communicatingdirectly with saidliquid immediately upon penetration of said diaphragm.

